Health Risk Appraisal Instruments (RAIs) are a burgeoning "industry" in health education, yet no properly designed and conducted scientific validation, or evaluation, of RAIs on a sufficiently large and representative sample of the general population appears to have been undertaken in the U.S., or elsewhere. The proposed three year study is intended to fill this gap. The study is divided into two logically related stages, each with its own specific research questions: Stage 1 focusses on aspects of the validity of currently available RAIs, while Stage 2 concerns the reliability and cost effectiveness of three representative instruments. At least the following major tasks will be undertaken: (1) Using computer simulation techniques, we shall determine how accurately RAIs represent an individual's actual cardiovascular risk (as estimated independently from the Framingham Heart Study data set); (2) Three RAIs (known to be valid and representative of different types of instrument) will be field tested to determine the validity of self-reported risk factor scores, the understandability and social acceptability of the RAIs and the variability of such issues among subgroups of the population, the reliability (ability to consistently reproduce scores/values) of the RAIs and the extent to which such reproducibility varies between instruments and among subgroups and the cost effectiveness of each RAI. The field test is a randomized 3 x 2 factorial design, with 225 subjects randomly assigned to each of the six treatment groups. The first factor represents the RAIs selected, including a general computerized health appraisal, a general self-scoring instrument and self-scoring heart disease risk assessment. The second factor represents presence or absence of feedback from the RAI. At least the following considerations motivate the proposed study: Absence of sound studies of the validity, reliability and cost effectiveness of RAIs already in wide use; The prototype offered by RISKO; The expertise and facilitative arrangements offered through PHHP; A need in health education to being more scientifically rigorous investigations.